LONDON - The first time Kristian Ipsen met Troy Dumais, Dumais smacked him in the face.

It wasn’t intentional, of course. Dumais was competing in the same diving meet where Ipsen, then 12 or 13 years old, was competing in the junior division. As Dumais warms up for his dives, he has a routine where he extends his arms out wide.

That’s when Ipsen walked past.

“And boom, he just hit me right in the face,” Ipsen recalled with a laugh. “I remember looking up and saying, ‘Oh my gosh, that’s Troy Dumais!’ I was kind of star struck. He was such an amazing diver and I was a really big fan. And it’s so weird to think now that he’s my partner.”

Strange? Maybe. But together, the combination – somewhat of an odd couple considering the 13-year age difference – makes a lot of sense. When Ipsen and Dumais compete Wednesday in the synchronized 3-meter at the Aquatics Centre, they will attempt to win Team USA’s third diving medal of these Games.

“We just have natural timing,” said Ipsen, 19, a Clayton, Calif., native who attends Stanford University. “And I think we complement each other well.”

The two were first paired together in 2009. At that meet, the coach mixed and matched different combinations to see which pairs fit.

“We were trying all things out,” said the 32-year old Dumais. “Then Kristian and I were paired together and it just worked. We’ve been together ever since.”

That year, the pair finished second in the world championships in 3-meter synchro. Dumais also won a silver in the individual competition. The two had not been able to train together consistently. Ipsen is in school in California and Dumais, who is from Ventura, Calif., works full-time at the University of Texas, his alma mater.

That changed this spring after Ipsen, then a freshman, became the first Stanford diver in 82 years to win a national title. The duo trained regularly in the weeks leading up to the Olympic Games and competed at several meets. During meets, they often shared hotel rooms.

“A lot of people ask me if that’s weird, rooming with someone so much older than me,” Ipsen said. “But we’ve become really good friends. He’s a mentor to me.”

A medal in London would cap off an incredible career for Dumais: He is the first American male to compete in four Olympic Games. Dumais has medals from world championships, Pan American Games, world cups and national meets. But at the Olympic Games, he has not finished higher than sixth in individual competition or fourth in synchro. Ipsen is an Olympic rookie.

“The age difference isn’t really an issue because we have the same goal,” Dumais said. “I just tell him to go out there and have fun. That’s the best advice I could give.”